Hello,
I am doing a test simulation of a ventilation cooling system of a barn using a convective heat transfer simulation. Here I have to define boundary conditions that change over time, specifically the velocity outlets. I have already seen that I can define boundary conditions that depend on the variable time (t(s)), but I was wondering if I can define boundary conditions dependent on the temperature (T(K)).
If it is possible I would thank you if you can give me a little explanation on how to define them.
Please bear in mind that if you need time changing boundary conditions, you should perform a Transient simulation. This might be very costly and hard to solve, so I suggest you to really think of the necessity of doing it.
On your question, you can not define a boundary condition such as velocity outlet to depend on temperature values. Are you trying to implement some kind of temperature controller here? If so, I think this is not the right approach to do it.
Hi, ggiraldof, thankyou for your reply. I am indeed performing a transient simulation since I need to know the evolution of the temperature over time. Also I am trying to implement a some kind of temperature controller and was thinking about how to do it using CFD simulations. What I really need to know is how many fans need to operate to cool down the domain at certain temperature setpoints.
If this is not possible to achieve using cfd simulations, do you have any idea on how can I do it?
You definitely need CFD to answer the question: How many fans are needed to drive the temperature from an initial to a final temperature? You can use a steady state simulation for this, by iterating the number of fans/flow rates and measuring the final value. If doing a transient simulation, you can additionally find the cooling period. Then you can use the resulting data, in the form of a transfer function, to design your controller.
Yes! Thank you that is what I need. Do you have any info or documentation about how to use the resulting data in the form of a transfer function? It would be really helpfull.
